Tension device for sewing-machines



(ModeL) H. HOLDEN, Jr. TEINSIONYDBVIGB FQR SEWING MACHINES. No. 297,799. Patented Apr. 29, 1884.

WITNESSES ATTORNEYS.

NITED STATES PATENT OFFICE.

HIRA-M HOLDEN, Ja, or SPENCER, MASSACHUSETTS.

TENSION DEVICE FOR SEW-ING-MACHINES.

SPECIFICATION forming part of Letters Patent No. 297,799, dated April 29, 1884.

' Application filed August 10,1833. (Modeh) To all whom, it may concern Be it known that I, HIRAM HOLDEN, Jr., of Spencer, in the county of WVorcest-er and State of Massachusetts, have invented a new and Improved Tension Device for Sewing-Machines, of which the following is a full, clear, and exact description.

My invention consists of improvements in tension devices for wax and dry thread machines, whereby it is designed to provide more efficient means therefor and better tension than other devices afford, and particularly to slack the tension while the needle is passing the thread through the work, and to arrange the tension device in duplicate, both of the tension-wheels being arranged on one supporting-stud, and so contrived that each may be adjusted for varying the tension without interfering with the other, all as hereinafter fully described.

Reference is to be had to the accompanying drawings, forming part of this specification, in which similar letters of reference indicate corresponding parts in all the figures.

Figure 1 is a side elevation of part of a sewing-machine with my improved tension device in side elevation. Fig. 2 is a front elevation. Fig. 3 is a section of the tension 7 device along the supporting-stud of the tenthe head A by the screw 9, said plate sup-' porting a long stud, h, about midway from top to bottom of said plate, said stud being for the support of the tension-wheels 'Z and j and the devices for regulating the tension of the same, which consists of the tube 70,- collar Z, spring m, and nut n for the wheel Z, washer 0, spring 19, and nut q for the wheel j The tension-wheels consist of a middle disk, 8, having a milled or roughened edge, to cause the thread to bind with sufficient friction to in-- tween wheel i and the plate f, and has a'studpin, y, which engages with plate f in any one of a series of holes, .2, arranged in a circle in said plate, by which to set the thread-guides higher or lower, as may be required. The tension-wheels are to be shifted back to allow the guide a to be shifted. The upper end of the plate f carries a stud, a, on which two collars, b, are fitted and adjustably secured by set-screws c, to which collars the take-up wires d are fitted, saidwires being coiled around said collars suitably to give said wires asensitive spring and for fastening them, and they extend downward in front of the tensionwheels, where they extend through slotted posts 6, projecting forward and a little upward from a flange, f, of the lower front part of plate f, and having adjusting-screws g, with check-nuts h, by which to limit the range of the movement of said take-up wires, which have guide-eyes 'Z in the end, through which the thread passes after passing through eyes at j in the lower ends of the posts 6. From the eyes 2" the thread passes through other eyes, k, at the lower end of flange f, and thence to the eye 0 of the guide d.

On thestud a, back of the plate f, a lever, Z, is pivoted, which extends downward in about the plane of the take-up wires, and carries an arm, m, which extends across the take-up allowing the take-up to spring back against gage-screws g and take up the thread again.

The needle is thus relieved of all strain by the thread while drawing the thread through the work, and thereby works easier and better. The dog a is so arranged that it swings down and passes the lever Z when the awl-bar rises. It then swings forward again, ready to act on the lever Z when the bar again descends. It will be seen that the tension-wheel may be adjusted for varying the tension by the nut n without affecting the tension of wheel j, and the latter may be adjusted by nut 11 without affecting wheel 2', its tension being governed by the pressure of the spring 1) between collar Z and nut q. To hold the tube It against turning on the stud h when the tension is in operation, or when the nut is turned to adjust the tension, a washer, s, for the inner end of the spring m is fitted to the fiat sides t of the stud, so that it cannot turn, and has a bit, u, fitting in a notch in the end of said tube. The lever Z has a plate extension, 12, overlapping plate f to some extent, and having a slot, 10, working along a studpin, w, of plate f, for a stop to limit the play of the lever by the dog a and spring q.

In the drawings a single-thread machine is shown; but this tension device is intended more particularly for application to double or two threaded machines, such as are used for sewing two seams at once.

I propose to employ this improved tension device either in duplicate, as here shown, or single, as may be required.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. The combination, with the plate f, having stud 71 and shifting tension-wheels ij, the

rod u, having guide-eyes, and a wax-cup or spool, of the supporting-arm or, pivoted on stud h between said plate and wheel Z, and having a stud-pin, 1, fitted in one of a circle of holes, 2, in said plate, whereby the threadguides may be set higher or lower, as described.

2. The plate f, having flange f, with eyes 7c, and stud a, with adjustable collars I) b, the take-up wires (1, coiled around said collars and having guide-eyes 'Z, the slotted posts 0, provided with adjusting device 9' h, and the guide d, having eye c,.in combination with the lever Z, having arm m, the pivoted dog a, the awl-bar having collar 1), with ears 0, and the needle, operated substantially as described.

8. The combination, in a tension device, of duplicate tension-wheels Z j, arranged on a stud, h, and provided with sleeve 7:, nut 11, spring 112, and washer s, for adjusting wheel 1', and collar 7, nut q, spring 1), and washer 0, for adjusting wheel j, substantially as described.

4. The tension-wheels ij, mounted on a stud, 71, attached to plate f, which plate also carries the take-up wires d and lever Z by the stud a, and also carries the guide-posts e and eyes 70 by flange f, and is adapted to be attached to the awl-bar-carrying head of a sewing-machine, substantially as described.

HIRAM HOLDEN, JR.

Vitnesses:

G130. W. LAoKnY, SCHUYLER D. CORBIN. 

